This invention relates to circuit interrupters, and more specifically relates to a novel arrangement for an arc spinner type of interrupter wherein an arc plasma is rotated at relatively high speed within a relatively stationary dielectric gas in order to interrupt the arc.
Arc spinner type interrupters are known in the art and are typically shown in U.S. Pat. No. 4,052,577, in the name of Gerald A. Votta, as well as U.S. Pat. No. 4,052,576, in the name of Robert Kirkland Smith.
In the typical arc spinner type of interrupter, an annular arc runner is provided which is perpendicular to the axis of the interrupter and this arc runner is closely coupled to an electrical winding which is arranged to conduct arc current during the arc interruption process. The coil induces a relatively high circulating current in the arc runner, and this induced current and the coil current produce a magnetic field in the arcing space. The magnetic field has a component which is perpendicular to the arc current, so that a Lorentz force is produced which tends to rotate the arc rapidly within the arcing space.
The arcing space is filled with a static dielectric gas, such as sulfur hexafluoride and the relative movement of the arc with respect to the gas causes the cooling and deionizing of the arc and the arc is extinguished at an arc current zero.
In arrangements of this type, the arcing space is a relatively confined space and the arc plasma tends to remain in this space, thereby increasing the deionization time and interfering with the deionization process for interrupting the arc current.